‘Considerable’ rates of lung cancer found among individuals with no known risk factors
A new study published in JAMA reveals “considerable” rates of lung cancer among individuals with no known risk factors.
Low dose computed tomography (LDCT) has been proven as an effective screening tool for lung cancer based on randomized clinical trials among seniors and current and former smokers. However, previous studies have shown rising rates of the disease for younger individuals and nonsmokers, especially in Asia, experts noted.
Researchers recently analyzed data from China spanning 2015 to 2021, looking at LDCT detection rates in the general population. They noted that lung cancer detection was similar for those at high risk of the disease compared to non-high-risk populations, based on National Comprehensive Cancer Network criteria.
“It is essential to test the generalizability of these findings in other regions and races (e.g., the U.S.),” Caichen Li, MD, with the Department of Thoracic Surgery and Oncology, First Affiliated Hospital of Guangzhou Medical University, China, and co-authors cautioned. “This study revealed that LDCT has a considerable detection rate of LCs in populations without known high-risk factors. These findings highlight the necessity of prospective studies to evaluate efficacy of CT screening and the importance of identifying high-risk factors or prescreen enriching biomarkers in populations not traditionally considered high risk.”
Li and co-investigators with Massachusetts General Hospital gathered their findings from the Guangzhou Lung-Care Project, a prospective intervention cohort study involving individuals ages 40 to 74. They excluded subjects with a prior LC diagnosis or treatment in the past five years, chest CT in the last year, or any notable cancer-related symptoms. This resulted in a study group of 11,708 participants including 16% classified as high risk for LDCT screening based on National Comprehensive Cancer Network consensus criteria and 41% according to Chinese Thoracic Society guidelines.
Lung cancer detection rates were about 2% among populations at high risk for the disease versus 1.6% for those who were not, based on National Comprehensive Cancer Network criteria. The figures were 2.3% and 1.3%, respectively, using the Chinese Thoracic Society recommendations. Similar trends were found when excluding cases of adenocarcinoma in situ, minimally invasive adenocarcinoma, or both. Meanwhile, the proportion of stage 1 disease for those diagnosed with LC was 60.5% for the high-risk group versus 92% in the other based on NCCN criteria and d 80.4% and 93.2%, respectively based on CTS standards.
“We found that the LC detection rate among individuals classified as not high risk was comparable to that of high-risk individuals, with a higher proportion of stage 1 cancer detected in the group without high risk,” the authors advised. “Although only 7 cases were adenocarcinoma in situ, potential overdiagnosis concerns remain, given 21.5% minimally invasive adenocarcinoma. Future research should focus on identifying the characteristics of LC that truly require therapeutic intervention to alter their prognosis.”
Read more details from the research letter in the Journal of the American Medical Association here.
Marty Stempniak has covered healthcare since 2012, with his byline appearing in the American Hospital Association's member magazine, Modern Healthcare and McKnight's. Prior to that, he wrote about village government and local business for his hometown newspaper in Oak Park, Illinois. He won a Peter Lisagor and Gold EXCEL awards in 2017 for his coverage of the opioid epidemic.